The NIH Collaboratory this week published a new chapter of its Living Textbook of Pragmatic Clinical Trials. The chapter, “Electronic Health Records-Based Phenotyping,” provides an overview of considerations for identifying, defining, and evaluating computable phenotypes for use with electronic health records (EHRs).

EHR-based phenotyping is an important strategy in large-scale pragmatic clinical trials, because these studies typically rely on standard phenotype definitions for EHR-based inclusion and exclusion of participants and consistent data analysis and reporting across data sources. Standardized queries of EHR data can be replicated at multiple sites, enabling efficiencies and ensuring that populations identified from different healthcare systems have similar features or were identified in the same way.

The new chapter includes the following sections:

• Introduction
• Definitions
• Finding Existing Phenotype Definitions
• Evaluating Phenotype Definitions
• Data Quality
• Using Phenotypes in PCTs—How Do I Get Started?

The new chapter updates a previous resource, one of the most popular on the Living Textbook, based on work by experts in the NIH Collaboratory’s Electronic Health Records Core Working Group (formerly the Phenotypes, Data Standards, and Data Quality Core Working Group).